Fiber that is wound on a bobbin normal (at right angles) to the bobbin axes will be payed out, or dispensed, in a spiral from a missile. Fiber that is wound on a bobbin with a full twist will be dispensed in a straight line from the missile. Full twist is defined as the amount of twist required to cause the fiber to be dispensed in a straight line.
Fiber that is payed out in a spiral is more likely to develop "kinks" and break than is fiber that is payed out in a straight line. From the standpoint of transmission losses due to changes in indices of refraction and losses due to microbending of the fiber, there will be certain advantages realized from optimizing the amount of twist on the fiber.
The present invention allows optical fiber to be wound on a bobbin with the twist varying continuously from zero (no twist) to full (360 degree) twist.